Water Saving, and More: the Benefits of Drip Irrigation

When we think about installing a garden, often what come to our mind first are the design and plants – which plants to select, where to plant them, and how they will look? While these are all very important, there is another equally critical aspect – how to keep the plants alive after they are planted? That points us to – the irrigation system, mainly, the sprinkler and drip.

The 2 systems

For irrigation of a garden, water is piped in. From the pipe, how to deliver the water to the plants? these 2 systems are the most common: sprinkler and drip.

Sprinkler is used for most of the lawns.

When the sprinkler system is used, not all the water go to the plants. Water might evaporate away, especially in hot and windy weather; another scene we might see often is runoff. The watering time might be too long; or the soil could only absorb so much water . Runoff is a waste of water that should be avoided.

Another irrigation system is drip. It points to the root system of a plant, and distributes water by “dripping” it slowly into the soil.

The Innovation of Drip Irrigation

Modern drip irrigation was invented in Israel in the 1950s. According to wikipedia, “a plastic emitter in drip irrigation was developed in Israel by Polish-born Simcha Blass and his son Yeshayahu. Instead of releasing water through tiny holes easily blocked by tiny particles, water was released through larger and longer passageways by using velocity to slow water inside a plastic emitter. The first experimental system of this type was established in 1959 by Blass who partnered later (1964) with Kibbutz Hatzerim to create an irrigation company called Netafim. Together they developed and patented the first practical surface drip irrigation emitter.”

More than half of Israel’s total land area is a desert, where water is scarce. Despite of this, Israel has a highly developed agriculture business. It not only produces enough food for itself, but also is a major exporter for fresh produce. How did they do it with so little water? Drip irrigation has been credited as the one innovation that contributed most significantly to this extraordinary achievement. The method allows water to be used so efficiently that large amount of corp can be grown and harvested with just the level of water in a desert.

Benefits of Drip Irrigation

As the example of Israel agriculture indicates, drip irrigation is a water efficient way for farming. It is also a water efficient way for gardening. There are some significant benefits of using drip irrigation.

Saves water

Water is delivered by “drips” right into the plant’s root area, with little runoff or evaporation. Almost all the water delivered is absorbed by the plants, translating to very high watering efficiency.

Runoff from a sprinkler irrigationNo runoff from drip

In California, outdoor landscape watering accounts for half of urban water usage. To save water, it is essential that we use water for outdoor wisely. Drip is the efficient way for outdoor watering.

On May 31,2018, California Gov. Jerry Brown signed into effect SB 606 and AB 1668. “In preparation for the next drought and our changing environment, we must use our precious resources wisely. We have efficiency goals for energy and cars – and now we have them for water”.

In the bill, a water use goal for indoor use is set. “Establishing an indoor, per person water use goal of 55 gallons per day until 2025, 52.5 gallons from 2025 to 2030 and 50 gallons beginning in 2030.”

A goal for outdoor will be announced in the near future.

2 years ago, when California was hit by the historical drought, Gov. Brown announced a mandatory 25% cut for the urban water use. The mandate was lifted when the drought ended. However, from that drought people come to realize how unpredictable the water situation can be, and how precious the water resource is. With the 2 bills signed, water conservation becomes permanent in California, not just an one-off effort.

In many cities, runoff from irrigation is prohibited legally. See the regulation in Santa Barbara:

“Irrigation with potable water that causes runoff onto adjacent property, non-irrigated areas, private and public walkways, roadways, parking lots, or parking structures is prohibited. Any excessive, unnecessary or unwarranted use of water is prohibited. All leaks must be repaired as soon as reasonably possible.”

It is very clear that we must use water wisely and efficiently in our daily lives. For outdoor use, switching from lawn and sprinkler to drip irrigation is one of important steps we can take, among all other measures.

Part of the Rebate program

Many water districts and companies offer turf conversion rebate programs. For a post-conversion landscape to qualify for the rebate, drip irrigation must be installed. Drip equipment may also qualify for rebates. This is what was specified in the Program Requirements for one such rebate program , Santa Clara Water District’s Landscape Rebate Program:

“Irrigation systems, if used within the converted area, must be low volume drip, micro-spray, or bubbler. The system must be in good working order, free of leaks and malfunctions. Once installed, the irrigation system must not create run-off, overspray, or misting.”

Works great with mulch

Chips in the mulch can be carried away by the spraying water from a sprinkler, which can expose the soil beneath and accelerate evaporation. With drip irrigation, as water will drip down slowly into the soil, it will not move the chips and mulch can stay for a long time.

In addition, when drip is used, much less water will be distributed on weeds compared with sprinkler. The precise positioning of drips means water is provided only to the plants, not to any others like weeds. This will prevent or slow the growth of weeds.

Saves time and effort

An automatic controller can be installed along with drip irrigation, so all the watering can be done automatically. With at least one emitter for one plant, all the plants will receive the water they need. Very little manual work will be required if all are set up correctly.

Installing Drip Irrigation

While drip irrigation can conserve water really well and saves time and effort, it requires advanced planning. Here are the major steps of installing drip irrigation for a new garden.

After the yard is prepared, lay out the plants at where they are supposed to be according to the plan.

Lay the pipes, install drip emitter for every plant.

Cover the pipes and the surface of the garden with soil and mulch. None of the pipes are visible now, only the beautiful plants!

Weather-Based Irrigation Controller and Rain Sensor

An automatic controller can be installed to automate the drip watering. The length and frequency of each watering can easily be entered from the touch pad of the controller.

To further conserve water, a rain sensor can be connected to a smart irrigation controller. When it rains, the information will be transmitted to the controller, which will then delay the next watering scheduled, avoiding the waste of the water.

Some controllers have mobile phone apps that work with them. After you download the app, you can view information or operate the controller from your phone, anywhere you go.

Gardens grew well with drip irrigation

Now we know drip irrigation can save water, how do they work for the plants? Do they grow well with such drip method?

The answer is positive. For the garden illustrated above, this was how it looked after the installation was done:

After just half year, plants grew big, a lot of them bloomed:

This was how a plant was like when it was first planted, a drip was installed for it:

After half year:

After a year and half:

This is another garden that was irrigated with just drip irrigation. This was when it was installed:

After just a year:

This Lion’s Tail grew from a small plant to a big bush in less than a year with the drip irrigation. Hummingbirds love its flowers!

In summary, drip irrigation can allow us to use water wisely for outdoor landscaping. Not only can we save water, plants can also grow well. If installed together with a smart controller and rain sensor, it can save even more water. Plant some drought tolerant plants, and install drip irrigation. We can have a beautiful garden with just a little water!